Last Call Working Draft of CCXML

The World Wide Web Consortium (W3C) has issued a last call working draft version of the Call Control XML 1.0 specification.

What is CCXML?

The Call Control eXtensible Markup Language (CCXML) is a standard for implementing call control in voice applications. It is meant to compliment the VoiceXML standard by providing control over higher level call features like creating and bridging different call legs, placing outbound calls and more. By contrast, VoiceXML is meant to handle the actual dialog that callers interact with.

In the absence of a call control standard, some VoiceXML platforms have implemented proprietary extensions that provide some of the functionality of CCXML. Others have implemented entirely different standalone languages with call control features. The adoption of a formal standard should make it easier form developers to build portable voice applications and incorporate the rich set of features available in CCXML into their voice apps.

Where is CCXML in the standards approval process?

Unfortunately, the process used by the W3C is somewhat of a labyrinth. My understanding of this process leads me to believe that after this “call” for comments, the specification will advance to “Candidate Recommendation” status, which should encourage more vendors to implement it in their platforms. Those with lots of time, or an inclination for self abuse ( 😉 ), can read more about the W3C approval process here.

Where can I learn more about CCXML?

Definitely check out the spec. The most comprehensive source of information on CCXML can be found on the Voxeo site. There are also some good tutorials on


I Like the Sound of These

There are some great resources on the web for developers wanting to learn more about voice applications, and for others who want to know what is possible with voice technologies. Here are a few of my favorites.

There is a huge trove of articles available on the site that features articles on VoIP, speech technology platforms and a large number of very good tutorials.

Ken Rehor’s World of VoiceXML has a large volume of information about voice technologies, including platforms, tutorials, presentations, links to the underlying specs and a lot more. Worth checking out — Ken is one of the authors of VoiceXML, and is currently one the Board of Directors of the VoiceXML Forum. He works for Vocalocity — the company that is the steward of the OpenVXI open source VoiceXML platform.

There is a site called HAWHAW (yes, that’s actually the name) that is home to one of the coolest PHP class libraries I have come across in a while. Its available for free, and is extremely useful for creating multimodal (voice and mobile) applications. There are some intuitive examples on this site that can help anyone with experience using PHP and some knowledge of OO programming get started creating mobile and voice applications. In a few weeks, I hope to have a tutorial posted demonstrating how to use this tool to create a simple application for local governments. The tutorial will demonstrate how to create a water meter reading submission application that can be accessed via the web, mobile phone (WAP) or by voice. Stay tuned…

The Age of “Open” Telephony

Are we entering a new age of telephony, one where the old rules don’t apply and new opportunities exist? Several developing trends suggest that the telephone industry (typically very slow to change) is headed for a big shake up. What is the catalyst for this change? Technology, of course.

Who can deny the impact that the development of open standards for phone-based applications – VoiceXML, CCXML, SRGS, etc. – has had on the vendor community. Are there even any vendors left that don’t support VoiceXML? One article discussing how these standards are creating new opportunities appears in the recent issue of VoiceXML Review. Its focus is a discussion of the feasibility of using CCXML to create a software PBX.

Other trends are also driving change, like the emergence of Voice over Internet Protocol (VoIP) and the maturity of new open source software products like Asterisk. A nice article discussing the impact that Asterisk is having on the telephone industry can be found on the O’Reilly OnLAMP site. There is also an interview with Mark Spencer of Digium (the company that makes Asterisk) available from CNET News. To put this trend into perspective, using open source tools like Asterisk:

With a Linux server, off-the-shelf LAN/WAN hardware, a broadband connection, and SIP-compatible telephone handsets, one can now build a fully functional telephone system, complete with high-end features.

Will the telephone industry ever be the same again? Probably not – and that is hugely important for governments as major users of telephone services. It’s also critical given government’s regulatory oversight and tax administration role over the telephone industry.

SOAP up your VoiceXML Apps

Both the BeVocal and Voxeo VoiceXML platforms incorporate the Simple Object Access Protocol (SOAP) and Web Services Definition Language (WSDL) specifications to provide some interesting options for VoiceXML developers.

Both platforms allow developers to create a proxy object for a web service by referencing a WSDL file for a given service. By doing this, developers can then access the methods of a web service as if it were simply a JavaScript object. The proxy object handles all the conversion necessary to transform a call to a JavaScript function to a SOAP method.

This functionality provides another way for developers to separate the presentation layer (in the case of a voice application, the rendering of VoiceXML) from the business layer. It also allows VoiceXML developers to access the wealth of different services available from web services providers. Developers should pay close attention to the implementation details provided on both he Voxeo and BeVocal sites.

One caveat, it appears that at least the BeVocal implementation works only with RPC-oriented services, not document-oriented services (support for document-oriented services is planned for a later release). Not sure if the Voxeo platform supports document-oriented services.

Municipal Broadband to the Rescue

It appears that Congress may soon weigh in on weather municipal governments should provide internet access by implementing large scale wireless broadband infrastructures. Philadelphia is among the governments that are leading the charge in this area, although some cities out west have been after this for some time now.

There are a number of arguments for and against municipal broadband initiatives – some hold water, some don’t. One of the more compelling for proponents (and repelling for opponents) is that municipal broadband initiatives will help bridge the “Digital Divide.” Dianah Neff, CIO for the City of Philadelphia, speaking in support of the City’s plan said:

Our focus is that 75 to 85 percent of our population in our low-income and minority areas that don’t have access. When we talked to them and we did surveys with them, they said 76 percent of the time that cost was the No. 1 reason why they didn’t have access to the Internet.

Those critical of such plans do make a good case on at least one point: simply providing access to the Internet does not address the number of other factors that challenge citizens in fully exploiting this resource. A number of other factors can impede a person’s ability to utilize the Internet – education, reading ability, general computer literacy to name just a few.

One of the significant benefits of using the telephone as a delivery mechanism for Internet service and content is that it can help address some of these basic computer and Internet acclimation issues. The degree of telephone literacy among citizens far out paces computer literacy – stated bluntly, phones are a lot easier to use than computers.

Who’s using phone voting?

Voting is one of the most fundamental activities of a representative democracy, yet the issue of Internet voting continues to be a contentious one for governments in the USA and Europe. The issue of phone-based voting is not new , although its consideration by and large predates the development of VoiceXML. Most current discussions of phone-based voting involve the use of cell phones with WAP technologies or text messaging.

Telephone voting is currently used in England (as is voting by text message). Some interesting information on the use of phone voting in England can be found here. I have read in some places that Oregon is testing telephone voting for absentee voters, but I’ve found no hard information on this.

An argument could be made that phone-based voting – using VoiceXML and related technologies – could go a long way towards addressing the issues raised in the current Internet voting debate.

VoiceXML and the Democratic Divide

An interesting paper appears in the Internet journal “First Monday” written by Stephanie Birdsall of Brown University discussing the issue of remote voting and its impact on political participation.

Ms. Birdsall makes some important observations about voting over the Internet, and the policy implications of the uneven distribution of Internet access (popularly referred to as the Digital Divide):

Problems with security, authentication, and privacy are generally cited as the more significant barriers to an online voting system, but even if those more technical problems were addressed, this paper argues that merging voting and ICT [information and communications technology] gives new relevance to the concerns raised originally by the emergence of the digital divide. Both voter turnout and Internet usage rates have well documented demographic components, income groups, racial groups, age groups, and education groups have different usage rates.

Internet use is not an ethereal, boundary–less activity, it is situated in a spatial/geographic context.

This is an excellent paper, and I agree with the concerns it raises. However, if it is fair to argue that Internet use does indeed happen in a physical place, its fair to point out that the “place” is less and less frequently in front of a desktop computer. Increasingly, governments are looking to alternative delivery channels for Internet based content and services, and telephones (as the most ubiquitous communications device of all) are an obvious consideration.

There is enormous potential for developing phone-based voting system that addresses issues of security, privacy and accuracy and also addresses the access issues raised by Ms. Birdsall. And while telephone penetration is still an issue in many areas, particularly with lower income citizens, penetration rates are significantly higher than for Internet-connected computers.

VoiceXML (most notably some of the features in the developing 2.1 specification) holds enormous promise for supporting a telephone-based voting system. Read my paper submitted to the National Institute of Standards and Technology on this subject (Word format).

In the next month, I’ll be releasing an open source implementation of the principles discussed in this paper – stay tuned.